In accordance with an exemplary scenario, several multi-radio systems-on-chip (SoCs) include multiple on-chip radio frequency (RF) circuits that coexist and operate on a single silicon die. Such SoCs include digital, as well as analog, circuits integrated on the same silicon die. For example, a SoC may be designed to accommodate Wireless Local Area Network (WLAN) systems, short range wireless communication systems, and Frequency Modulation (FM) radio systems thereon.
In various exemplary scenarios, the RF circuits coexisting on the SoC may cause interference issues in efficient operation of the SoCs. For example, the digital circuits in the SoC may significantly contribute to the interference when the harmonics of the frequencies of a digital clock signal associated with the digital circuits fall in a band of interest of RF circuits. As such, the RF circuits may not function as expected. In various exemplary scenarios, such harmonics of the frequencies of the digital clock signals are referred to as spurs or spurious signal. If the spurs caused by digital activity happen to be in the band of interest of RF circuits on the SoC, they may cause degradation in the performance of RF circuits. For example, the spurs may change the noise floor, thereby impacting the detection of channel presence. In so much as the location of the interfering frequency band may be closely related to the digital clock frequency, choosing the digital clock frequency may be difficult.